1. Field of the Invention
The present embodiment relates generally to a device for excavating and separating objects from a medium in which such objects are located. In particular, the present embodiment relates to a device for digging and sifting to be used in conjunction with a metal detector.
The following is a tabulation of some prior art that presently appears relevant:
U.S PatentsPatent NumberKind CodeIssue DatePatentee  915,233Mar. 16, 1909Smith2,960,230Nov. 15, 1960Fracker3,976,564Aug. 24, 1976Holder4,979,623Dec. 25, 1990Flanagan7,878,334Feb. 1, 2011Tucker
U.S. Patent Application PublicationsPatent ApplicationNumberKind CodePublication DateApplicant20060180512A1Aug. 17, 2006Allen
2. Description of Related Art
Metal detectors make it possible to quickly and easily locate buried objects which may then be retrieved. Although many devices have been developed for retrieving buried objects, there exists a need in the art for a device that is lightweight, durable and easily repairable. Prior art devices used for retrieving buried objects typically include scoops, spades, shovels, sieves and the like, however, not all of these devices are best suited to retrieving buried objects while metal detecting. Devices designed specifically for digging and sifting while engaged in the hobby of metal detecting have a scoop-like design with fully or partially welded structures. The use of welding for assembling a scoop has significant limitations. Metals with different compositions cannot be reliably welded together. Welds in general, or the metal next to welds, are prone to fail due to fatigue.
There are numerous examples of known art disclosing scoops made specifically for retrieving buried objects while metal detecting. These scoops, while varying in shape, size, construction techniques, and use of materials, all have fully or partially welded structures. Much of the art discloses scoops with fully welded structures, while some of the art discloses partially welded structures with bolted and/or riveted on accessories. Metal detecting scoops, whether fully or partially welded, taught by the known art, all have their key structural components welded together. Key structural components are defined as those scoop parts of the known art that are currently being welded. Thus, a construction technique utilizing welding limits a scoop's key structural components to materials of the same composition. For example, the key components of a scoop constructed using a welding process should be all stainless steel composition or all aluminum composition, but not a combination of both stainless steel and aluminum composition. Aluminum alloy cannot be reliably welded to stainless steel alloy. And most high strength light-weight aluminum alloys, suitable for use as the key structural components of a scoop, cannot be reliably welded to themselves.
In addition, the key structure of a welded metal detecting scoop using materials of the same composition is subject to failure at the welded connections. Welds eventually fail due to over-load, underdesign, or fatigue as a result from the shrinkage strains that occur as the weld metal cools. When a welded scoop fails at its welded connection, the result is a weakened scoop that cannot be easily repaired by the user. Repairs to scoops that require additional welding continue to contribute to the weakening of the scoop due to the same strains that occurred as the weld metal cooled during the original weld. Some repairs even require adding more material and structure to the scoop, inherently increasing its overall weight.